1. Field of the Invention
This invention relates to propulsion units for electrically powered rail vehicles. In particular, it relates to a hollow beam that encloses the propulsion motor and the torque-transmitting means for connecting the motor to a driven axle, the beam having an opening large enough to insert the motor and the torque-transmitting means into the beam at one end to allow the beam to serve as a common housing and, simultaneously, to provide improved torsional and flexural strength to the propulsion unit.
2. The Prior Art
Propulsion units as shown in DE-OS No. 23 25 789 and DE-OS No. 23 64 594 include housings for the stator of the propulsion motor and for coupling means by which torque is transmitted from the motor to the driven axle or axles. The mechanical designs of the housings, which are connected to each other, are shaped to correspond to the propulsion components contained in the respective housings as far as the outside dimensions are concerned. The necessary boundary conditions, such as the support structure for pinion shafts in the torque-transmitting apparatus and the arrangement of the undercarriage cross beam, result in constrictions due to the limited space available and thus have a detrimental effect on the stability of the propulsion units.
British Patent Specification No. 1 438 620 describes propulsion units for electrically actuated rail vehicles, having separate housings for the motor and torque-transmitting means.